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Trends in Customer Activity
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Trends in Customer Activity

EasySQL · PostgreSQL

Problem

How would you write a query to find trends in customer activity by date?

Use the activity records to produce one daily summary. Exclude records where the activity date is missing.

Output

  1. One row per activity date
  2. Columns: activity_date, total_activities, and unique_customers
  3. Sort by activity_date from earliest to latest

Schema

customer_activity
ColumnTypeDescription
activity_idPKINTUnique identifier for the activity record
customer_idINTIdentifier of the customer associated with the activity
activity_dateDATEDate on which the activity occurred
Tablescustomer_activity
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